BOOM - that'll be 1 o'clock then

This is the one o'clock gun as it goes off, well almost as I jumped out my skin as it was set off and that photo was all blurred, so this is approx. 1/2 second after it had gone off.

for those who don't know

The gun was established in 1861 as a time signal for ships in the Firth of Forth, and complemented the time ball, which was installed on Nelson's Monument in 1852 (Calton Hill), but which was useless during foggy weather. The gun could easily be heard by ships in Leith Harbour, 2 miles (3.2 km) away. Because sound travels relatively slowly (approximately 343 metres per second (770 mph)), maps were produced in the 1860s to show the actual time when the sound of the gun was heard at various locations in Edinburgh